Rivet detonating tool



1952 w. c. STRATMAN ET AL 2,618,399

RIVET DETONATING TOOL FIG.

- IN VEN T015 WILL IQM 0. STRA TMAN JOSEPH l4. F/SGHER MM- Km A TTORNEYPatented Nov. 18,

UNITE. S

RIVET DETONATING TOOL William C. Stratman and Joseph W. Fischer, LosAngeles, Calif., assignors to North American Aviation, Inc.

Application August 6, 1949, Serial No. 109,014

2 Claims.

This invention pertains to a device for detonating explosive rivets.Rivets of this type are well known in the art and constitute, generally,an arrangement whereby blind riveting can be accomplished by the use ofan explosive charge contained within the rivet. Difficulty has beenexperienced in satisfactorily detonating these rivets to the extent thatit is now common practice to use soldering irons and blow torches forthat purpose. This is an expensive and somewhat dangerous expedient and,accordingly, it is an object of the present invention to provide amechanism by which these rivets can be detonated easily and quickly.

It is another object of this invention to provide an arrangement whichis quite effective and yet safe from an operative standpoint.

It is yet another object of this invention to provide a rivet detonatorwhich is relatively inexpensive, easy to maintain, and of long life.

Other objects of invention will become apparent from the followingdescription taken in connection with the accompanying drawings, in whichFig. 1 is an elevational view of a rivet gun incorporating the presentinvention, and

Fig. 2 is a sectional view of the rivet-holding and detonating part ofthe gun taken at line 2-2 of Fig. 1.

Referring to the drawings, I and 2 represent plates or sheets ofmaterial which are to be fastened together by rivet 3 of the explosivetype. To accomplish detonation of the rivet, gun 4 is adapted to holdthe rivet in place and at the same time impart to it a high frictionalforce such as will cause detonation. Gun 4 may be essentially ahigh-speed air-driven rotary drill motor capable of producingapproximately 20,000 revolutions per minute. The details of theoperating mechanism of the motor which produces rotary motion are notshown because they are conventional in the art. For the purposes of thisinvention, however, this gun includes a chuck 5 for drivingly holding aspindle 6 mounted rotatably in member 7, which in turn carries collar 8and is integral with casing 9. Casing 9 is carried by forward extension22 of the casing of gun and is connected thereto by a nut 2i in a mannerwell known in the art. Casing 9 may be provided with slits at the endthereof to contract it upon member 22 as is customary in this art ifdesirable or necessary to attach casing 9 to 22. Casing 9 may also beprovided with a window for purposes of using a chuck key on chuck 5 tofasten or unfasten spindle 6 in the chuck, all in a mannor common to theart. A sleeve I9 is slidably received in member 1 and held againstrotation by ball H located in recess l2 of member I, and slot [3 ofsleeve ID. A recess M is provided in collar 8 to permit assembly anddisassembly of this arrangement by forward movement of member I withrespect to collar 8 to permit ball II to be received in recess M,thereby permitting sleeve H! to be withdrawn from member 1. Ring [5limits inward movement of member 7 on collar 8. Springs l6 and I! holdthe various parts in extended adjusted position. Sleeve It) may beprovided with a tip I8 of phenolic or fibrous material for betterholding the rivet in position, although it is to be understood that thistip can be omitted if desired. Spindle 6 is also provided with a tip [9of phenolic or other material having a high coefficient of friction forthe purpose of better detonating the rivet 3. This tip may be omitted ifthe spindle is made of suitable material.

In the operation of the arrangement, rivet 3 is placed by hand, orotherwise, in aligned openings in members I and 2, whereupon the tip [8of gun 4 is brought into contact with the head of the rivet to hold itin place. Thereupon the body of the gun is pressed forwardly to causerelative retraction of sleeve in against spring ll to bring the tip 59of spindle 6 into engagement with the head of rivet 3. High-speedrotation of spindle 6 and tip l9 results in the generation of sufiicientheat to cause detonation of the rivet. The holding of the rivet firmlyin place while being detonated insures a proper seating of the rivet,prevents rotation of the rivet and consequent scoring of the materialbeing fastened, and affords a safety feature to the operator. Spring I?is designed to resist a predetermined force such as will properly holdthe rivet in place against rotation when engaged by tip is, and tofirmly seat the rivet to insure proper functioning thereof whenexploded.

It is to be understood that the detonating gun may take other forms andshapes and that, although the invention has been described andillustrated in detail, the same is by way of illustration and exampleonly, and is not to be taken by way of limitation, the spirit and scopeof this invention being limited only by the terms of the appendedclaims.

We claim:

1. A rivet detonating tool for use with a drill motor having a fixedcasing and a relatively r0- tatable chuck, a sleeve slidably carried bysaid casing, a tip having a high coefiicient of friction 3 4 carried byand rotatable with said chuck, and UNITED STATES PATENTS spring meansurging said sleeve outwardly be- Number Name t yond said tip to seat andhold an explosive rivet, 444,721 Bevington Jan, 13, 1391 said sleevebeing retractable against the action of 1,299,137 Davis r, 1, 1919 saidspring to allow said tip to rotatably engage 5 ,70 02 Hawn Mar, 26, 1929said rivet to heat the same and thereby explode 2, 2,935 schlack Oct.26, 1943 the same as the result of the heat produced by 2,3 9,492 RepperFeb. 13, 1945 the friction of said tip upon said rivet. 2,426,275 KrebsAug. 26, 1947 2. A device as recited in claim 1 in which Said 2,477,056Gookin July 2 9 tip is formed of phenolic material. 10

WILLIAM c. STRATMAN. FOREIGN PATENTS JOSEPH W. FISCHER. Number CountryDate 20,473 Great Britain Dec. 20, 1889 REFERENCES CITED The followingreferences are of record in the 15 file of this patent:

